1. Technical Field
The present invention relates to an electrophoretic display.
2. Related Art
One of displays is an electrophoretic display which performs display in such a manner that charged particles (that is, electrophoretic particles) dispersed in a dispersion medium contained in microcapsules are electrophoretically moved with electric fields generated between electrodes and the distribution of the charged particles is controlled. In general, such an electrophoretic display has a structural advantage in that the electrophoretic display is suitable for thickness reduction because electrophoretic particles have high reflectivity and therefore any light source such as a front light is not necessary and also has a qualitative advantage in that the electrophoretic display has a large viewing angle and high contrast. Furthermore, the electrophoretic display has an advantage in that the electrophoretic display is suitable for low power consumption because any back light is not necessary or a voltage need not be applied between electrodes for the purpose of retaining a display state. Because of these advantages, the electrophoretic display is attracting much attention as a next-generation display device and is under active development (see, for example, JP-A-2010-20231).
In order to allow the electrophoretic display to quickly perform display switching (that is, high response) or to have increased display contrast, a large electric field needs to be generated between electrodes. Furthermore, the electrophoretic display is required such that a display state is retained as long as possible after the application of a voltage is stopped.
However, for electrophoretic displays having microcapsules (that is, a capsule structure), the following guidelines have not been established or specified: guidelines specifying what electrical properties materials used inside and outside the microcapsules should have in order to increase the intensity of electric fields in the microcapsules or in order to increase the retainability of a display state.